The invention relates to a holder of rectangular shape which comprises two main walls and three side walls interconnecting the two main walls, and is open at a fourth side, which holder is adapted to receive through the open side a rectangular cassette with a record carrier contained therein in order to protect the cassette and, at the location of at least one side wall comprises a clamping member for clamping a cassette inserted in the holder, which clamping member is connected to the holder at the location of said side wall, comprises a part which projects into the holder interior and is made of an elastic material and, via the part which projects into the holder interior, can be partly deformed elastically by a cassette inserted in the holder.
For such a holder, been proposed to construct the clamping member as a plug-type member of an elastomeric material and to snap the clamping member with an annular groove formed in this member into a hole in the relevant side wall of the holder. In practice, such a clamping member can be manufactured by means of a moulding process. When a cassette is inserted into the holder and cooperates with the clamping member comparatively large elastic deformation occur which deformations when the clamping member extends through the relevant side wall cause the clamping member to protrude outwardly, i.e. to form a bulge, which is undesirable not only for cosmetic reasons. The bulging sides will prevent a close and space-saving stacking of the packages. This may be particularly harmful in automatic cassette changers. Moreover, with such a plug-type clamping member the likelihood of the member being inadvertently pressed out of the hole in the side wall is comparatively high.